Compressor



Aug. 17, 1937. A. E..BIERMANN 2,090,230

COMPRESSOR Filed Sept. 10, 1935 2 Sheets-Sheet 1 WITNESSES INVENTOR 1M Vow Patented Aug. 17, 1937 UNITED STATES PATENT OFFICE oomanssoa Arnold E. Bicrmann, Hampton, Va. Application September 10, 1935, Serial No. 39,913

Claims.

This invention relates to gas compressors or power producing engines of the rotary type, and the main object is to provide a compressor or engine of compact construction and efllcient 5 operation.

- Owing to inherent features of construction the volume capacity of my device is much greater than that of other machines of this class having the same overall dimensions. In my device it is 1 possible to handle in a single cycle of operation several times the volume of the compression chamber.

An object of this invention as used for compressing fluids such as air is to provide in this type of machine means for trapping and isolating each charge of gas to be compressed and means for reducing the volume of the'trapped chargeuntil the pressure is raised to a predetermined outlet pressure before communication with the discharge port is established. To those familiar with the art it is evident that maximum eihciency is obtained in this type of compression. Work is done against a pressure which increases continuously fromvthe inlet pressure to the discharge pressure.

In all previous pumps of this class compression of the inducted charge takes place with the charge in constant communication with the discharge port. Work is always done against the full discharge pressure. As is well known in the art, such a condition gives rise'to a square indicator card andis very ineiiicient. i

Furthermore, in these last mentioned pumps throttling losses occur when the high pressure gas in the discharge line rushes back into the chamber containing the low pressure charge. These throttling losses are not present in my de-v vice as communication is not established between the chamber in which the charge is being compressed and the discharge line until the pressure in the former is raised to that of the latter.

A further object of this inventionis to providemeans in this type of gas compressor for varying the point-of intake cut-off and in this manner control the quantityof gas pumped. Inconsequence, the power required'for compression is very nearly proportional to the quantity of fluid pumped. Other compressors of this class, due to properties inherent 'in their construction, must resort to other means of control such as throttlingthe intake. It is evident that in these other compressors the power required maysbe much in excess of the power required 'to coinpress the quantity of gas desired. The compactness, efficiency, and controllabll- .in Figure l and serve as bearing supports for the rotor shaft 5 and also provide means for attachity of my device make it especially desirable for supercharging aircraft engines. In this service it is necessary to provide means for changing the volume capacity-of the compressor to meet the requirements at various altitudes. 5

Another object of this invention is to provide a suitable and ready means for changing from a I compressor to an engine or from an engine to a compressor, the same means being also adapted to changing the compression ratio when used as 10 a compressor and the point of exhaust opening when used as an engine. In the accompanying drawings Figure 1 is a side view in elevation and partly in section of a compressor constructed in accordance with the 15 principles of my invention; Figure 2 is a viewin perspective of a rotor, rotor shaft. and impeller assembly; Figure 3 is a diagrammatic view to show the principles of operation; Figure 4 is an end view in elevation with the housing partly cut away; Figure 5 is a view in perspective of a rotary valve; Figure 6 is a view in perspective of a rotary valve control sleeve; Figure 7 is a view in.perspective of a sleeve cam for manually con-- trolling the rotary valve port opening.

Referring to Figures 1 and 4, l designates a housing constructed in two parts; fastened together to form a torus-like chamber to which are attached the spiral abutments 2. Side members 3 and I are secured to housing I as shown ing respective intake and discharge pipes.

Referring now to Figures 1, 2 and 4, the rotor 6 is fixed to the rotor shaft 5 by means of the rotor shaft flange I. The outer rim of the'rotor 6 is circular and constructed to provide bearings 8 for the impeller shafts 9. The impellers ID are mounted on -shafts 9 and are adapted to rotate through the slots ll provided in the web 40 and'rim of the rotor 6. The impellers l0 are provided with the radial slots H which associate with the spiralabutments 2. These slots are relieved sufliciently at the outer portions as to allow rubbing contact with'the spiral abutments 45 2 only at the inner slot portions II where the angle between the impellers I II and the spiral abutments 2 is more favourable for rotation-of the impellers by the abutments.

Referring to figures 1 and 4, each spiral abut- 50 ment 2 extends from one side'of the web ll of the rotor 6 around the torus-like housing I in spiral fashion to the opposite side of the web I 4.

The shape of each spiral'abutment 21s such as would be generated by the slot I! of an im- 55 peller I as-the impeller moves with the rotor 6 at a uniform speed about the axis of the rotor while at the same time the impeller Ilirotates about its ,own axis at a uniform speed such as to generate a predetermined number of whole spiral abutments in one revolution of the rotor.

This manner of generation gives the device-a smoothness of operation but requires that the abutments be made of thickness varying along their lengths. This results from the fact that the angle of the spiral occupied by the abutments varies from a minimum nearest the rotor axis to a maximum where it is farthest from that axis. The angle of slot I2 through impeller Ill, however, is fixed; and where the direction of slot motion deviates most from its angle, the slot will develop the thinnest shape for the abutments.

Referring to Figures 1, 4 and 5, the rotary valves I5 and I6 are of similar construction and are secured to the rotor web I4 for rotation adjacent to the base portion I! of the spiral abutments 2.

The rotary valves I5 and I6 are constructed with a series of ports I 8 and I9. The valve portions 20 and 2| between the ports are parallel to the adjacent spiral abutments 2. The width of the' ports I8 and I9- is less than the width of the base portion ll of the spiral abutments 2.

Referring to Figures 1, 5, 6 and 7, controlsleeves 22 and 23, which are of similar construction, are rotatably mounted inside and adjacent to the rotary valves l5 and I6 and are provided with openings 24 and 25. The sleeves 22 and 23 provide a means for adjusting the expansion and compression ratio of the compressor, adjustment being accomplished by rotation of the sleeves relative to the rotary valves I5 and I6 respectively. Any suitable means may be utilized for controlling the angular position of sleeves 2'. and 23. Forpurposes of illustration I show and describe a simple manually controlled means which is of similar construction for both sleeves 22 1 and 23. 'Sleevecams 33 are rotatably mounted on shaft 5' and are fastened to the control sleeves 22 and 23. Said sleeve cams are provided with the cam slots 32. Control shafts 26 are slidably 1 mounted in hole 21 in shaft 5 and are provided with pins 28 adapted to extend through slots 30' in shaft 5 and through cam slots 32 in sleeves 33. Collars 34 are slidably mounted on shaft 5 and are fastened to control shafts 26 by ,means of sleeves 33 causes angular movement of control sleeves 22 or 23 with respect to the rotary valve I5 or I6 respectively.

The torus-like housing [is-provided with ribs 38 for strengthening and to obtain additional cooling area.

The operation of my invention: is as follower- As the rotor 6 rotates, association of the impellers III with the spiral abutments 2 causes rotation of the impellers III about their axes. In

this-movement the portion of each impeller I ll between spiral abutments 2 sweeps eachcham- ,ber formed by the spiral abutments 2, the housing I, the rotor 6, the intake valve I I and the discharge valve I6.

The detailed cycle of operation is best understood by means of the diagrammatic view shown in Figure 3. In this view the inside of the toruslike housing is stretched out flat showing the spiral abutments 2, the impellers III, the rotary intake valve I5, the discharge valve I6, the intake valve control sleeve 22 and the discharge valve control sleeve 23.

In operation as a compressor the impellers I6, the rotary valves I5 and I6, and the control sleeves 22 and 23 effectively move in the direction shown by the arrows while the abutments 2 and the housing I remain stationary.

' It will be noticed in Figure 3 that when the impellers arrive at a position in which the chamber volume is a minimum the inlet ports also arrive at the same chamber and establish communication with that chamber. Then as the impeller moves to increase the size of the chamber additional ports communicate with the chamber and gas is inducted. when the last inlet port which is exposed by the control sleeve 22 has passed the chamber the charge is trapped and is expanded and then compressed as the chamber volume passes through its maximum. When the discharge ports arrive at the chamber communication is established with the chamber and the gas is forced out of the chamber by the impeller. It will be noticed that the position of the intake valve control sleeve 22 regulates the interval of the cycle that the chamber is in communication with the inletpipe and so regulates the quantity .of gas trapped in the chamber. The position of the discharge valve control sleeve 23 regulates the point in the cycle when open discharge ports I9 arrive at -the cham-.

ber and therefore regulates the degree to which the charge is compressed before communication is established with the discharge pipe.

To further illustrate the operation, A is a chamber just receiving gas through the rotary intake valve I5 and control sleeve 22; the cham-'- ber B is still receiving gas but is nearing the point of cut-off; in C the gas has been trapped and expanded to its full volume; the'gas in D is being compressed; while in E the compressed gas is being discharged through the rotary valve I6 and the control sleeve 23.

It is evident from Figure 3 that moving the control sleeve 22 on the inlet side forward will cause cut-oil to occur at a smaller chamber volume resulting in a smaller quantity of gas being pression pressure for any speed of operation of the compressor. v

For these reasons it is evident that such a compressor isespecially useful as a supercharger for an internal combustion engine. Furthermore when used in conjunction with an internal combustion engine at part load the supercharger may be used as an engine for taking part of the engine I 1 load by adjusting-the control sleeves to give a discharge pressure less than the intake pressure. The supercharger is thus used at part engine loads to throttle the intake to the engine and thevwork which is done by the gas on the supercharger in expanding from the inlet pressure to 1. In a device of theclass described a housing having a torus-like recess, one or more spiral abutments fixed to the surface of the housing within said recess, a rotor mounted for rotation in said'housing in close association therewith to form a toroidal chamber, one or more impellers mounted for rotation in said rotor and adapted to 'movein close association with said spiral abutments and the, surfaces of said housing and rotor 'to form substantially gas-tight compartments adapted tovary in volume cyclically from zero to a maximum and to zero again as the rotor is revolved, inlet ports in said rotor adapted to provide communication with' said compartments,

. only during expansion of said compartments from zero to a given volume, outlet ports in said rotor adapted to provide communication with said vcompartments only during contraction of said compartments from a given volume to zero volume, and means for selectively adjusting each of said given volumes to any value between zero and the said maximum.

' 2. In a device of the class describeda housing having a torus-like recess, one or more spiral abutments fixed to the surface of the housing within said recess, a rotor mounted for rotation in said housing in close association therewith to form a toroidal chamber, one or more impellers ,mounted for rotation in said rotor and adapted to move in close association with said spiral abutments and the surfaces of said housing and rotor to form substantially gas-tight compartvments adapted to vary in volume cyclically from zero to a maximum and to zero again 'as the rotor is rotated, inlet ports in said rotor adapted to provide communication with said compartments during expansion of said compartments from zero to a predetermined volume, means for varying the size of the inlet ports for controlling the maximum volume attained by the compartments while still in communication with the-inlet ports, outlet ports in said rotor adapted to communicate with said compartments during contraction of said compartments froma predetermined volume to zero, and means for varying the outlet portsize for controlling the volume of the compartment at which communication is. first established with the outlet.

having a torus-like recess, one or more spiral abutments" fixed to the surface of the housing within said recess, a rotor mounted for rotation in said housing in close association therewith to form a toroidal chamber, one or more impellers mounted for rotation in said rotor and adapted 'to move in close association with said spiral abutments and the surfaces of said housing and rotor to form substantially gas-tight compartments adapted to vary in volume cyclically from zero to a maximum and to zero again as the rotor is rotated, inlet ports in said rotor adapted to provide communication with said compartments during expansion of said compartments from zero to a predetermined volume, means for vary- 3. In a device of the class described a housinging the size of the inlet ports for controlling the maximum'volume attained by the compartments while still in communication with the inlet ports,

outlet ports in said rotor adapted to communicate with said compartments during contraction of said compartments from a predetermined volume to zero volume.

4. In a device of the class described a housing having. a torus-like recess, one or more spiral abutments fixed to the surface of the housing within said recess, a rotor mounted for rotation in said housing in close association therewith to form a toroidal chamber, one or more impellers mounted for rotation in said rotor and adapted to move in close association with said spiral abutments and the surface of said housing and rotor to form substantially gas-tight compartments dapted to vary in'volume cyclically from zero to a maximum andto zero again as the rotor is rotated, inlet ports in said rotor adapted to provide communication with said compartments as said compartments vary in volume from zero to a predetermined volume, outlet ports in said rotor adapted to communicate with said compartments as said compartments vary involume from a predetermined volume to'zero, and means for varying the outlet port size for controlling the volume of the compartments at which communication-is first established with the outlet.

5. In a device of the class described a housing having a torus-like recess, one or more spiral abutments fixed to the surface of said housing within said recess, a rotor mounted for rotation in said housing in close association therewith to form a toroidal chamber, one or more slotted impellers mounted for rotation in said rotor and adapted to move in close association with said spiral abutments'and the surfaces of said housing and rotor to form compartments adapted to;

vary in volume as the rotor is rotated, the slots of said impellers being relieved at the outer portions a suflicient amount to .allowrubbing contact of the impellers with thetip portions only of said spiral abutments.

6. In a device of the class described a housing having a torus-like recess, one or more spiral abutments fixed to the surface of the housing within said recess, a rotor mounted for rotation in said housing in close association therewith to form a toroidal chamber, one or more impellers mounted for-rotation in said rotor and adapted to move in close association with said spiral abut-.

ments and the surfaces of said housing and rotorto form substantially gas-tight compartments adapted to vary in volume as the rotor is rotated, inlet ports in said rotor extending from each impeller in the direction opposite to the direction of rotation of the rotor a predetermined distance, a movable control sleeve mounted adjacent to said inlet ports to vary the distance said inlet ports extend from the impellers, outlet ports in said rotor extending from each impeller in the direction of rotation of the rotor a predetermined distance, a movable control sleeve mounted adjacent to said outlet ports to vary the distance said outlet ports ex tend from the impellers, grid v bars extending across said inlet and outlet port openings in a direction parallel to the adjacent spiral abutments and spaced to provide openings within said recess, a rotor mounted for rotation in said housing in close association therewith to form a toroidal chamber, one or more impellers mounted for rotation in said rotor and adapted, to move in close association with said spiral abutments and the surfaces of said housing and rotor to form substantially gas-tight compartments adapted to vary in volume as the rotor is rotated, inlet ports in said rotor extending from each impeller in a direction of rotation opposite to the direction of rotation of the rotor a predetermined distance, a movable control sleeve mounted adjacent to said inlet ports to vary the distance said inlet ports extend from the impellers, outlet ports in said rotor extending from each impeller in the direction of rotation of the rotor a predetermined distance, a movable control sleeve mounted adjacent to said outlet ports to vary the distance'said outlet ports extend from the impellers.

8. In a device ofthe class described a housing having a torus-like recess, one or more spiral abutments fixed to the surface of the housing within said recess, a rotor mounted for rotation in said housing in close association therewith to form a toroidal chamber, one or more impellers mounted for rotation in said rotor and adapted to move in close association with said spiral abutments and the surfaces of said housing and rotor to form substantially gas-tight compartments adapted to vary-in volume as the rotor is rotated, inlet ports in said rotor extending from each impeller in the direction opposite to the direction of rotation of the rotor a predetermined distance, a movable control sleeve mounted adjacent to saidinlet ports to vary the distance said ,inlet ports extend from the impellers; outlet ports in said rotor extending from each impeller in the direction of rotation of the rotor a predetermined distance.

9. In a device of the class described a housing having a toroidal chamber, one. more spiral abutments fixed to the surface of said.- chamber, a rotor mounted'in said housing for rotation with respect to said toroidal chamber, one or more impellers rotatably mounted in the rotor and adapted to move in close association with respect to said spiral abutments and the surface of said toroidal housing, said impellers, spiral abutments and housing combining to form chambers of variable volume, ports in said toroidal housing communicating with said toroidal chamber, a

rotary valve fixed to each side oi said rotor and having ports of variable size for communication with any chamberof variable volume in saidtoroidal housing during prescribed intervals in the cycle. 7

10. In a device of the class described a housing having a toms-like recess, a disc rotatably mounted in said housing, said disc having an enlarged rim section, rotary valves mounted to turn with said disc and to fit in close association with said recessed housing to. form a toroidal chamber, spiral abutments fixed to the surface of said torus-like'recess and extending from one side of said disc to the opposite side, slotted impellers rotatably mounted in the rim of said disc in engagement with said toroidal chamber and spiral abutments to form compartments of varying volume as said disc is rotated, the slots of said slotted impellers being relieved at the outer portions a sumcient amountto allow rubbing contact with the free edge portion only of said spiral abutments, inlet and outlet means in said rotary valves on opposite sides of said disc providing communication with said compartments only during prescribed intervals in the rotation of said disc.

11. A device of the class described comprising a housing having a torus-like recess, a disc mounted for rotation in said housing, rotary intake and discharge valves mounted concentrically with respect to said housing and on opposite sides of said disc and extending therefrom to flt in close association with said recessed housing to form a toroidal chamber, means for supporting and rotating said disc, slotted impellers mounted in the rim of said disc, spiral abutments oi longitudinally varying thickness attached to the inner surfaces of said housing and so disposed as to continually fit said slots of said impellers as said impellers rotate about their axes and revolve with said disc simultaneously, ports 'in said intake and discharge valves of variable size for communication with any portion of said housing only during prescribed intervals in the cycle.

12. In a device 01' the class described a housing having a toms-like recess, a disc rotatably mounted in said housing, said disc having an enlarged. rim section, rotary valves mounted to turn with said disc and to fit in close associati on with said recessed housing to form a toroidal chamber, spiral abutments fixed to the surface of said torus-like recess and extending from one side of. said disc to the opposite side, slotted impellers rotatably mounted in the rim of said disc in engagement with said toroidal chamber and spiral abutments to form compartments oi varying volume as said disc is rotated, said disc hem! constructed of two similar parts providing means when fastened togetherior mounting said slotted impellers in the rim of said disc, inlet and outhaving a torus-like recess, spiral abutments fixed to the surface of said housing. a slotted disc mounted for rotation in said housing, rotary intake and discharge valves mounted concentrically with respect to said torus-like housing and on opposite sides or said disc and extending theretrom to flt in close association with said recased 7 housing to form a toroidal chamber, slotted impellers rotatably mounted in the rim and slots of said disc in engagement with said housing and spiral abutments forming substantially gas-tight compartments wherein the volume is varied cyclically from zero to a maximum and to zero again as" said disc is rotated, intake ports in said rotary valve on one side of said disc providing intake means into said compartments during expansion of said compartments from zero to a given volume, discharge ports in the other said rotary valve providing discharge means from said compartments during contraction or said comrim section, rotary valves mounted to turn with said disc and to fit in close association with said recessed housing to form a toroidal chamber, spiral abutments fixed to the surface of said torus-like, recess and extending from one side of said disc to the opposite side, slotted impellers rotatably mounted in the rim of said disc in engagement with said toroidal chamber and spiral abutments, said spiral abutments being one more in number per said impeller than there are slots per impeller.

15. In a device of the class described a housing having a torus-like recess, a disc rotatably mounted in-said housing, said disc having an enlarged rim section, rotary valves mounted to turn with said disc and to fit in close association with means in said rotary valves on opposite sides of said disc providing communication with said compartments only during prescribed intervals in the rotation of said disc adjustable control sleeves mounted adjacent to said inlet and outlet ports to vary the distance said ports extend from said impellers, and grid bars extending across said inlet and outlet port means in a direction parallel to the adjacent spiral abutments and which are spaced to provide openings between said grid bars of a width not less than the 10 thickness of the adjacent portion 01. said spiral abutments.

ARNOLD E. BHIRMANN. 

